Desulfoferrodoxin: a modular protein

作者：Ascenso C; Rusnak F; Cabrito I; Lima MJ; Naylor S; Moura I; Moura JJG^*

来源：Journal of Biological Inorganic Chemistry, 2000, 5(6): 720-729.

DOI：10.1007/s007750000161

• desulforedoxin
• desulfoferrodoxin
• rubredoxin
• neelaredoxin
• superoxide
• oxidoreductase

The gene encoding the non-heme iron-containing desulfoferrodoxin from Desulfovibrio vulgaris was cloned in two fragments in order to obtain polypeptides corresponding to the N- and C-terminal domains observed in the tertiary structure. These fragments were expressed in Escherichia coli, purified to homogeneity and biochemically and spectroscopically characterized. Both recombinant fragments behaved as independent metal-binding domains. The N-terminal fragment exhibited properties similar to desulforedoxin, as expected by the presence of a Fe(S-Cys)(4) metal binding motif, The C-terminal fragment, which accommodates a Fe(N-epsilon-His)(3)(N-delta-His)(S-Cys) center, was shown to have properties similar to neelaredoxin, except for the reaction with superoxide. The activities of desulfoferrodoxin and of the expressed C-terminal fragment were tested with superoxide in the presence and absence of cytochrome c, The results are consistent with superoxide reductase activity and a possible explanation for the low superoxide consumption in the superoxide dismutase activity assays is proposed.

• 出版日期2000-12